The Enemy on Board
by Tripidydoodah
Summary: This story explores what might have happened if, in the episode "The Enemy Within", the positive version of Captain Kirk had been killed by the negative one during their fight in sick bay, and what difference it would make to the next episode, "The Naked Time".


**The Enemy on Board**

 **(Some dialogue from certain episodes has been used. There is no intent to supersede anyone's rights.)**

On the bridge, Kirk's double was quite at home in the Captain's chair.

"Prepare to leave orbit, Mr Farrell!"

"Captain?"

"I gave you an order, Mr Farrell."

The helmsman couldn't believe Kirk would leave without Sulu and the rest of the landing party. "What about...?" he asked.

"They can't be saved. Prepare to leave orbit!"

"Yes, Sir."

"Captain, I thought..." Spock began.

"I changed my mind. Return to your station, Mr Spock!"

Like Farrell, Spock also couldn't believe that the Captain would callously abandon four of his crew to their deaths. Unlike Farrell he knew that Kirk had been split in two by a transporter malfunction, and began to suspect that the order had been given by Kirk's negative alter ego. But what was he doing on the bridge when he was supposed to be under restraint in sickbay? While Spock was trying to come up with a reasonable hypothesis, Dr McCoy stepped through the turbo-lift doors and approached the man in the Captain's chair. "Sir, please come with me to sickbay," he said. He spoke quietly, but with difficulty, as if he were trying hard to hold on to his emotions.

The Double turned to face McCoy. "I can't be bothered with that now, Doctor. We're preparing to leave orbit," he blustered. "Return to your post." There was fear in The Double's expression but he appeared to have more control than previously, which surprised the First Officer.

McCoy stayed his ground, giving Spock a chance to take a good look at his face. The doctor looked ghastly but his expression was clearly telling Spock that he needed his help. Realising that something was terribly wrong, Spock took the only logical action possible and administered a Vulcan nerve pinch to the Captain's right shoulder, catching the slender body as it slid towards the deck.

"Doctor McCoy, the Captain has collapsed," Spock said. "Please help me take him to sickbay. Mr Farrell, you have the con. Tell Mr Scott to beam up the landing party from the planet's surface immediately."

"Aye, aye, Sir," Farrell said, with relief. It was obvious now that the Captain must have been ill when he gave the order to leave orbit. He hoped Dr McCoy was able to get him back on his feet.

Spock lifted the unconscious human with ease born of Vulcan muscle and headed for the turbo-lift. McCoy followed him.

As soon as the door closed behind them McCoy grabbed the control and said, "Sick bay!"

"Perhaps you can explain how the Captain's double came to be on the bridge?" Spock said. "His presence almost resulted in a catastrophe. He had already given the order to abandon the landing party."

McCoy sagged against the wall. "It's worse than that, Spock," he rasped. "Jim's dead!"

Spock lurched imperceptibly and his face began to crumple, then suddenly became even bleaker than before. A sense of great loss swept over him and he wanted nothing more than to be alone to grieve. However, he could not forget that the ship and crew were now his responsibility. "Doctor, please go to the transporter room and make sure that the landing team are all right. I shall deal with the Captain."

"Blast you, Spock. How can you be so cold-blooded at a time like this?"

"Since my indulging in an emotional display will not bring Jim back, his memory will be better served by my concentrating on the problem at hand."

"Which is?"

"What we are to do with his double."

On arrival in sickbay, Spock carried the Captain to one of the secure units and dropped him on the bed. Thankfully Nurse Chapel was nowhere in sight. He employed the bed restraints to prevent the human from escaping again, and left the room, securing the door lock behind him. Aware that his Vulcan calm was slipping away from him, his one thought was that he had to find Kirk's body. He presumed it would be in the room where they had imprisoned his double earlier.

Spock walked over to the bed where the body of his friend lay. The Vulcan's face was even stonier than usual, hiding the ragged tear in his Vulcan control. It was hard for him to believe that just a few hours ago Dr McCoy had accused him of analyzing James Kirk's guts. He stared down at the familiar face, bruised now and with the addition of scratches, mirroring those on the face of his double.

McCoy entered the room. "Some of the landing party have frostbite but they're going to be all right," he said. "I've left Dr M'Benga to deal with them."

Spock nodded in acknowledgement but his gaze remained on Kirk's face.

"It hurts, doesn't it?" McCoy said.

"How did it happen?" the Vulcan asked.

"It looks like his double attacked him after Jim released him from the restraints. In his weakened condition Jim couldn't have put up much of a fight. His double scratched his face so that we wouldn't be able to tell them apart. He was still alive at that point."

"How did he die?"

"I can't say for sure without a post mortem but, when I found him, he was lying on the floor and it was obvious, from his injuries, that his head had been smashed against the bulkhead more than once. My guess is that the blows caused a fatal bleed in his brain. It would have taken a matter of only minutes for him to die."

"Then his double may not have intended to kill him?"

"It's possible but what does it matter? The result's the same."

"It matters," Spock replied.

McCoy looked puzzled at Spock's words but the Vulcan didn't elaborate so, shrugging, he voiced the question that had been on his mind for the last hour or so. "What will you tell the crew?"

"That the Captain is suffering from a recurrence of Rigelian Kassaba fever."

"Even if they believe you, it will only buy you a day."

"If it had been treated in time," Spock suggested.

"Okay, a week at most, but you can't keep him hidden forever. You'll have to inform Star Fleet eventually."

"On the contrary, I will inform no-one of this. It must go no further than we two and Mr Scott. As far as the crew is concerned, the double is the Captain and he will remain in that position."

"Are you out of your Vulcan mind, Spock?"

"What would you have me do, doctor? He is as much Jim as his positive side was."

"Yes, well..." From the look McCoy gave him it was obvious he was having a hard time accepting that fact. "But without his other half, his good half, it's just not possible for him to function as Captain of the Enterprise."

"Consider the alternative, doctor. If the truth were revealed it would soon spread throughout the galaxy and Captain Kirk would become the focus of curiosity, even pity. At worst he would be studied and become nothing more than a laboratory specimen. At best he would be dismissed from Starfleet and his career would be over."

McCoy turned on him. "You can't let him loose on the Enterprise. Look what he did to Yeoman Rand... and Jim."

"I do not intend to 'let him loose', as you put it. Obviously, his personality will have to be modified first. Apart from the fact that the Double appears to express only negative emotions, he has the same brain function and nervous system as any other human. Theoretically, he could be made to take on the attributes that his positive half possessed. He has already learned a certain amount of control, which indicates the odds are in our favour."

"But it's only a theory, Spock. Don't forget Jim couldn't take on the attributes he needed to command this ship."

"I'm not so sure, Doctor. He was weak-willed and indecisive but, when it was imperative that he take action, he not only refused to resign his command but he did, in fact, make the decision to reunite with his double, even though his negative side disgusted him."

"I accept that, but what would motivate his double to develop positive qualities?"

"I shall persuade him that he must change if he wants to be accepted as Captain of the Enterprise. But first we have to keep him alive. I suggest you concentrate on that."

McCoy cleared his throat. "I may be able to help there," he admitted.

"Explain."

"From the start we realised that neither of them could survive without the other and I wanted to be prepared if there was a problem with uniting the Captain's two halves. So I've been working round the clock, trying to synthesize a drug to counteract the effects of the transporter malfunction."

"Were you successful?" Spock asked.

"Well, the split affected the physiological and mental processes, making it quite a challenge to halt the inevitable degeneration in both."

"Doctor, do you have such a drug or not?"

"Yes, but there's no way of testing it."

"No matter. If we can halt the degeneration, it could theoretically make it easier for the double to gain his missing personality traits," Spock pointed out.

"You could be right, but what if it kills him?"

"Logically we have no choice except to use it. We cannot be in a worse situation than we are now. However, we still have to persuade 'the Captain' of that."

"He's regaining consciousness," McCoy announced.

The Double opened his eyes with a groan and then noticed the straps holding down his arms and legs. The muscles in his face tensed and he gritted his teeth, the fear overtaking him at finding himself a prisoner again.

Spock placed his hands on either side of the Double's head and forced him to make eye contact. "Captain, you are in sickbay. Dr McCoy is here. You are safe. Do you understand?"

The Double moistened dry lips. "I understand, but I don't trust you. You sided with the other one against me, took my ship away from me."

Spock released his hold. "Your opposite was the logical choice to deal with the problem created by the transporter," he explained. "He was the only one of you capable of acting rationally."

"You told the crew I was an imposter."

"That was the only possible explanation that the crew would accept. They could not be told the truth. It would have undermined their faith in the Captain's ability to command."

"Logical as always," the Double sneered. "Do you still plan to force us back together? Where is that snivelling version of me anyway?"

There was a sharp intake of breath from McCoy. "If you mean the half of you that had all the noble qualities, he's dead. You killed him!"

"I didn't...," the Double began, then he recalled the fight, the other Kirk's head in his hands, hitting it against the bulkhead, a knockout blow. "His head...I didn't mean to..."

Spock intervened. "Leaving aside the fact that you were prepared to kill him on the engineering deck, I am willing to accept that, in your unbridled anger and hatred for your opposite half, and your fear of being reunited with him, you hit him harder than you intended. In any case, it is not my intention to report the incident to Starfleet."

The Double relaxed and Spock found himself the recipient of one of Kirk's familiar, slow-burning smiles. "Good old Spock," he said. "I knew I could count on you."

Spock raised one eyebrow in response, whilst realising two things. Firstly, the man in front of him had his fair share of James Kirk's charm and, secondly, that he would need to be on his guard, as this version was not above using it for devious means.

"Tell him, Spock!" McCoy urged.

"Tell me what?" the Double demanded, panic returning.

"Because we cannot reunite you with your other half, you will inevitably weaken and die, within a short period of time."

"No!" The Double looked desperate. "I don't want to die. I want to live. Don't let me die!" he pleaded.

"If you become agitated it will speed up the process," Spock said, calmly.

His words had the desired effect on the Double, who slowly won the fight to control his panic and managed to ask, "Is there anything you can do?"

"Dr McCoy has prepared a drug that will hopefully cure the problem."

"What do you mean 'hopefully'?"

"It is as yet untried."

"I don't care. Give it to me!"

"It's not as simple as that," McCoy said, dryly.

"Why not?"

"Reciprocation is necessary," Spock said.

All he got in return was a puzzled look.

"If you want the medication, you have to agree to do what we want," McCoy explained.

The Double looked suddenly wary. "You're not taking my ship away from me," he rasped.

"On the contrary," Spock assured him, "It is my intention to restore you to your position as Captain of the Enterprise."

"You seem to forget I'm already in command of this ship," the Double said.

"I wouldn't try issuing any orders, if I were you," McCoy rasped. "The results of any psych test you were to undergo would be sufficient reason for me to relieve you of that command."

"Spock?" the Double appealed to his first officer but the Vulcan remained silent.

McCoy was pleased to see that the Double was puzzled and suspicious. It was best to keep him off balance as much as possible.

"Okay, what is it you want?" the Double capitulated.

"You have heard Dr McCoy's view," Spock said. "That because of the effects of the transporter malfunction, you are not capable of commanding the Enterprise. In order to do so, you would have to regain the attributes you lost when you were split in two, logic, integrity, compassion..."

"Yeah, so how am I supposed to do that?" the Double broke in.

"I suggest that you start by learning about the person you were before the split by using your shared memories. Dr McCoy will administer the drug if you will agree to submit to a Vulcan mind-meld. And don't deceive yourself that, once you have been given the medication, you can change your mind. I will have no compunction about using force, if you resist."

The Double looked horrified by the idea. "No way am I going to let you crawl around inside my head," he shouted, becoming agitated again.

"That is your view. I will not argue with it. I will simply reiterate that without the meld, you will not receive the medication."

"What if the drug doesn't work?"

"Then you would die and there would be no point in going ahead with the mind-meld," Spock pointed out.

"It looks like you have me over a barrel," the Double snarled. "Let's get on with it then."

"I will take that as your agreement to what I have proposed."

"Take it any way you want. Just get it over with."

"Dr McCoy?" Spock said.

McCoy came forward with a hypo and pressured the contents into the Double's arm.

"Is that it?" the Double asked.

"Yes," McCoy said. "You must be tired after today's events. If I were you, I'd take the opportunity to get some sleep."

"Aren't you going to remove the restraints?" the Double queried. "I feel so weak and I wouldn't be able to go anywhere with the door locked anyhow, now would I?" He gave a tired smile.

Spock had to stop himself from saying 'fascinating', at this sudden volte face on the Double's part. He realised how easy it would be for this human to manipulate him. Did he try it on Jim as well? Spock was certain he had because it would explain how he managed to get free. Spock paused to gather his Vulcan mental cloak around him and said, "I regret I am not willing to take the risk. I know how resourceful you can be."

"Come on Spock, I thought we had an agreement?" The Double was wide awake now.

"Quite and, as you have now benefitted from our side of the bargain, it would be illogical, on my part, not to make absolutely sure that you remain here to fulfil yours."

There was no reply from the Double. He simply glared at the first officer. Obviously he didn't react well to being thwarted.

"Sweet dreams," McCoy said, adding insult to injury.

Then they were gone, leaving the Double alone with his own troubled and twisted thoughts.

Spock decided to go to his quarters for a period of meditation, in preparation for the mind-meld. But first he informed the crew that the imposter had been dealt with. McCoy had been persuaded to phaser Jim's body out of existence, to avoid awkward questions. To McCoy, it felt like the Captain was dead; he just couldn't seem to bring himself to think of the Double as James Kirk and began to wonder if he ever would. It was up to Spock to work a miracle and McCoy hoped he was up to the job. Otherwise there would be a lot of explaining to do to Starfleet Command.

The Double opened his eyes with a groan and attempted to stretch his arms above his head, at which point he was painfully reminded that there were straps holding him down. He was consigning Spock and all his forebears to a much hotter place than even the planet Vulcan itself, when the door opened and the object of his wrath entered, accompanied by Dr McCoy.

By this time the Double had realised that neither of them was going to let him get away with anything. Losing his temper hadn't worked with Spock, in fact quite the opposite. For the moment he was content to let his overriding need for the Enterprise push him into the bargain with the Vulcan. He had to appear harmless, in order to get them to trust him. He concentrated his thoughts...'control, control, control...'

"I've brought you something to drink," McCoy said. "You must be pretty thirsty by now." He held a glass of green liquid to the Double's lips. "Drink it all, it'll do you good."

The Double complied. He thought it best to obey the doctor and, anyway, he was thirsty.

"How are you feeling?" McCoy asked when he had finished. The Double couldn't help noticing that, unlike the Vulcan, the doctor never used his name or title.

"I'm just a little tired," the Double replied, with a small smile, while struggling against his baser instincts. He hoped that his words and expression would make them think he was no threat,

"That's not surprising, after all you've been through," McCoy said, concentrating on the display above the bed. "Your vital signs are stable, except that your blood pressure is definitely on the high side."

"Could it be caused by the drug you gave me?" the Double asked.

"Could be," McCoy said. "I'd like to see the work-up on the blood sample I took earlier before I rule out anything."

The Doctor was impressed by the way the Double managed to sound so controlled and reasonable and wondered if, when Jim had imbued his double with some of his strength, in order to keep him alive, he might also have instilled some of his logic into him.

The Double was also remembering that episode in sickbay, when his opposite had held his hand and promised never to let go. He had thought him a weak fool and had planned at that moment to turn his weakness against him. The opportunity had come sooner than expected.

"Is the Captain strong enough to undergo the mind-meld?" Spock asked.

"I guess so," McCoy answered.

"Then please proceed."

McCoy removed a hypo-spray from his medical pouch.

The Double was taken by surprise and so had little chance to put up much resistance as the hypo hissed against his arm. "What the...," he began.

He heard Spock say, "Thank you, Doctor, you may wait outside," and the doctor's reply of, "I'm going. But, for the record, I don't like this."

"So noted," Spock said.

Spock and the Double were now alone.

Once the door had closed behind McCoy, Spock sat down on the bed. The Double looked confused.

"I suspect that you are having difficulty in speaking," Spock said. "Dr McCoy has injected you with something to render you more cooperative. It relaxes the muscles, including the ones needed for speech. However, it will not affect your thought patterns."

The Double's confusion tried to turn to anger but the drug he'd been given made it hard to solidify the emotion. That pointy-eared...!

Spock remembered that Jim had described his opposite as a thoughtless, brutal animal. The Vulcan silently prepared himself for what he would find in the meld, trusting that the drug would dull the effect of any violent emotions. His sense of ethics rebelled at what he was going to do. Added to that, he disliked the fact that it had been achieved through coercion. Even under normal circumstances it was seen as an invasion of privacy, distasteful to his race, and not to be used lightly.

As the human tried, and failed, to keep out of his reach, Spock took a deep breath, focused his thoughts and placed his fingers on the Double's face, feeling for the correct position to initiate the meld. The Double felt a tentative mental touch in the top layer of his mind which slowly steadied and became stronger, as Spock met and dealt with the emotions that the Double couldn't keep from him. Through the mixture of fear and hatred, Spock sensed a strong need for self-preservation. He moved slowly through that layer, calming the fear and deflecting the hatred. He was surprised to encounter feelings of loneliness and a longing, that the human tried to hide, but for what, Spock could not tell and he didn't linger, in case it involved Yeoman Janice Rand. The mind-meld had a purpose and it was not to pry into the Double's private thoughts and feelings, well only as much as absolutely necessary, he conceded.

Spock was now ready to go deeper. "My mind to your mind," he intoned.

His priority now was to help the Double learn the qualities of his positive half, by forcing him to recall memories of his experiences, prior to the split. At first the human attempted to resist the deep probe but he was no match for the Vulcan's determination. Nevertheless, Spock realised his task would not be an easy one.

Spock brought up Kirk's memory of Planet M113.

" _What's going on?"_

" _I intend to tap into the memories you share with your opposite, so that you can observe the emotions involved and learn from them. Please pay attention."_

The Double offered no further resistance but Spock could sense his unwillingness.

Star date 1513.1. - Spock was temporarily in command while the Captain beamed down to planet M113, with Dr McCoy. The landing party were standing in front of a grey, stone building and Kirk was teasing his colleague about Nancy Crater, that one woman from the doctor's past.

"Do you want to pick some flowers, Doctor? When a man visits an old girlfriend she expects something like that."

"Is that how you get girls to like you, by bribing them?" McCoy teased in turn, causing Kirk to laugh.

" _As if I ever have any trouble getting girls to like me,"_ came through the meld _._

The scene switched to sickbay and Darnell's body. Kirk was talking to Doctor McCoy. "...I've lost a man. I want to know what killed him."

Spock saw the names flashing through Kirk's mind. Darnell, Green, Sturgeon, Barnhart - all dead. Sadness and regret flowed in, tempered with the knowledge that this was undeniably the risk men took when they signed up with Starfleet.

" _At least_ _ **I**_ _was still alive,"_ came from the human on the bed _._

" _There was a time when you were prepared to risk your life for your crew and your ship,"_ Spock prompted _. "Remember Gary Mitchell? It was a hard decision for any human. On the one hand your duty to your ship and crew, on the other the life of your best friend."_

Star date 1313.1. The Enterprise was in orbit around Delta Vega. Kirk and Spock were discussing Helmsman Gary Mitchell who had acquired extremely strong ESP powers, after the Enterprise hit an energy barrier. It was obvious that his presence was becoming a threat to the ship but he was also a personal friend of Kirk's and had been for fifteen years. Nevertheless the Captain had to decide what to do with him.

"What I need are recommendations, Mr Spock, not vague warnings."

"You have one other choice, kill Mitchell while you still can."

"Get out of here!" (Spoken softly but with anger.)

"It is your only other choice, assuming you make it while you still have time."

"Will you try for one moment to feel? At least act like you've got a heart. You're talking about Gary."

" _I remember the words but what is that weird feeling?"_ the Double asked _._

" _It is compassion for your friend."_

" _Command and compassion is a fool's mixture!_ _"_

" _Those were Mitchell's words, not yours."_

" _They're still true. I should have killed Mitchell before he became so strong. I let compassion get in the way."_

" _You did not always dismiss the need for compassion."_

" _So you want me to be more like that bleeding-heart version of myself that you liked so much?"_

" _You do him a disservice. He had the logic to accept that he needed your half. But he also recognised that it needed to be properly controlled and disciplined. When you were part of him, he would not allow you free reign and neither will I. It is imperative that you learn to control your emotions and desist from treating humans as of no account. You need compassion, among other things, to achieve that."_

" _I can control my emotions, if I want."_

" _To deny the facts is illogical. I refer, of course, to your conduct toward Yeoman Rand."_

Suddenly Kirk was back in Janice Rand's quarters. There was a half-empty bottle of Saurian brandy in his hand, the liquid that had fuelled his uncontrolled lust.

The unexpected presence of the Captain in her room and the burning intensity of Kirk's appraisal made Yeoman Rand nervous. "Captain?" she queried.

"Jim will do here, Janice."

The furnace-like quality of Kirk's thoughts as he relived the scene, made Spock retreat and the memory was gone, leaving a resonance of the heat of Kirk's need, tinged with a wistful longing which had been denied.

" _What's wrong?"_

Spock was suddenly aware of how much his friend had tempered his emotions when around him. This one had no such restraint. He sought out an earlier image of Yeoman Rand.

The scene changed again. This time Kirk was talking with McCoy in the captain's quarters when Yeoman Rand brought in his lunch. It was obvious that Kirk didn't appreciate her ministrations and, after he had dismissed her he said, "If I get my hands on the headquarters genius that assigned me a female yeoman..."

"What's the matter, Jim, don't you trust yourself?" McCoy teased.

Kirk's was silent for some moments as if he was considering the idea for the first time. But he was the pre-split Kirk and he had his darker side under control.

"I've already got a female to worry about. Her name's the Enterprise"

Spock could sense that the Double was only thinking of Janice Rand and the point of the recollection was totally lost on him. He gave a mental sigh before reaching for a memory which would catch the human's attention.

Star date 1329.1 - The Enterprise had taken on board four passengers, Harcourt Fenton Mudd and his cargo, three stunningly beautiful women, who undoubtedly were having an extremely magnetic effect on the male crew members. Kirk was just as vulnerable as anyone else, but keeping a tight lid on his reactions. Unbeknown to the crew, the women's allure was enhanced by the use of an illegal substance called the Venus drug.

" _As a Vulcan you were totally immune of course."_

" _I found the extreme reaction of the crewmen most curious."_

" _I could always tell when you were laughing at our human failings. You should know that you really don't hide your emotions as well as you think."_

 _Caught off-balance by the fact that his friend had kept that knowledge from him, Spock determined to try harder in the future to project the correct degree of Vulcan control. Meanwhile he had more pressing business..._

The scene switched to the Captain's quarters where Kirk entered and found one of the women, Eve McHuron, lying on his bed, waiting for him. Kirk approached but remained on the other side of the screen that divided his sleeping quarters from the working area.

"Captain, I hope you don't mind."

"In fact, Miss McHuron, I do."

 _He'd felt ridiculous, talking to her through the screen. He wasn't used to finding beautiful women in his cabin and he was a little unsure of how to deal with her, at the same time trying to maintain control over his libido. There was a sudden blend of memories as the Double recalled how he had hidden behind the screen in Janice Rand's quarters for a completely different reason... Spock cut the memory off and steered the Double's thoughts back to the scene with Eve._ Suddenly she was on his side of the screen, talking about loneliness and the responsibility of having the crew look up to him.

"I read once that a commander has to act like a paragon of virtue. I never met a paragon," Eve said.

Kirk gave a little laugh. "Neither have I"

"Well of course not, no-one is. Some people try to pretend," she put her arms around his neck. "You, Captain."

It was then that Kirk was certain she was trying to seduce him. "M-m-miss McHuron, I don't...," he stuttered, still fighting for control.

She tried to pull his head down into a kiss. He strained to keep his face away from hers, but she was difficult to resist.

" _Why didn't I take what she was offering? No-one would have cared!" the Double said._

" _It is not right to just take what you want, whether it is offered or not. You cannot live your life acting on a purely instinctive level."_

" _Acting on instinct is part of being in command of a starship."_

" _Nevertheless, there is a moral code which must be adhered to if you want to live among civilized beings. Remember what happened next."_

Kirk was back in his quarters and Eve was pulling away from him. "Oh, no, I just can't do it!" she said, and ran from the room.

To Kirk, Eve's words were like a jug of cold water in the face.

 _Suddenly the realisation of why he had forced himself to resist her slammed into the Double's mind. "My ship!" he exclaimed, "I had to focus on reaching Rigel XII. Without the lithium crystals the Enterprise would have been stranded. The Enterprise, she had to come first, before any other female."_

" _Perhaps now you understand the necessity of controlling your emotions. Only then will you be able to employ the logic needed to make command decisions."_

 _As the Double lay almost helpless under his touch, Spock forced himself to ignore his own conscience and the code of honour he had learned, as a Vulcan, and directed the link toward the part of the Double's brain that was the source of his emotions. He was bombarded with the ugliness of anger, jealousy, hatred and fear. But he could also sense the seeds of morality and duty that he had attempted so carefully to plant there, and a surprising longing to be liked. There was also a question._

" _What the hell are you doing, Spock?"_

" _I am establishing a link between our minds. It will allow me to monitor your emotions and prevent the repetition of your unsavoury behaviour."_

" _No, I won't permit it."_

" _I am not asking for permission."_

 _The Double resisted him. "Go climb a tree, Spock!"_

" _Captain, you have no choice. If you ever want to command the Enterprise again you must allow me to do this."_

 _Spock had hit upon the most persuasive argument possible. He found it interesting, yet ultimately logical, that the thing common to both the positive and negative Kirk had been their identity as Captain of the Enterprise. Logical because James Kirk had needed his positive and negative sides in order to command effectively. Both of them had fought to stay in command of the ship. The Vulcan felt the Double falter as he considered the impossibility of giving up his command, and swiftly moved in to establish the low-level link._

" _It is done."_

With regret for what he had had to do, Spock slowly withdrew from the human's mind, moving gently, leaving behind the new thoughts and feelings, he had nurtured. It would have to be enough. He looked down at the human but the human refused to look at him.

"I'll send in Dr McCoy." Spock said.

With mask in place, Spock walked out of sickbay.

McCoy was hovering outside. "Well?" he demanded.

"You can release him now, doctor. To all intents and purposes he is James T Kirk, Captain of the Enterprise, and he will be treated as such."

So the Vulcan had noticed his reluctance to use Kirk's name or title. "All right," he grumbled. "I just hope you know what you're doing."

"So do I, Doctor, so do I," Spock replied.

Doctor McCoy found a subdued Kirk. "How are you feeling?" he asked. All he received in acknowledgement was a shake of the head. He undid the straps binding the Captain's arms and Kirk clumsily brought up his left arm to cover his eyes.

"The sedative should wear off completely in a few more minutes," McCoy said, releasing Kirk's legs from their restraint. "I suggest you stay here and get some rest. Do you want anything to eat?"

Kirk shook his head.

"Just give it time," McCoy advised.

Kirk looked directly at the doctor. "Time enough for that Vulcan to reprogram me, you mean."

"No, it's not like that. All Spock wants to do is safeguard the ship and the crew if you decide to go off half-cocked, like you did on the bridge."

"But I'm the Captain. He threatened to take the ship away from me. I don't want that Vulcan in my head."

"You're wrong; Spock's the best friend you've got. I wanted to hand you over to Starfleet but he wouldn't hear of it. Instead he's put his career on the line for you. If Starfleet ever find out what happened...well."

"But you didn't agree with what he did to me," Kirk countered.

"Because the link he forged with you is against his Vulcan code of honour and is every bit as distasteful to him as it is to you, probably more so. Spock told me had never used a mind-meld on a human before. As a Vulcan, do you think he enjoys prying into your private thoughts and feelings, being bombarded with human emotions?"

"Does he know everything I'm thinking?" Kirk demanded.

"No, you needn't worry about that. As Spock explained it to me, he will only monitor your thoughts when it's necessary. Of course, he'll automatically sense any strong emotion or loss of control on your part."

Kirk remained silent, his gaze fixed on the wall opposite."

"I should get some rest, if I were you," McCoy said. "You've had one hell of a day."

Kirk nodded and closed his eyes. When the doctor was gone, he lifted his head and his eyes were filled with a mixture of self-pity and hatred for his first officer.

In the period since the mind-link had been initiated several things had happened. Spock had erected a mental version of a 'Keep Out!' sign where Janice Rand was concerned and, as a precaution, she had been told to report to Kirk only when he was on the bridge. Bearing in mind the involvement of Saurian brandy in his attack on her, Kirk was under strict orders to drink alcohol only in the presence of his Chief Medical Officer. Humiliatingly, even his personal replicator had been modified to prevent him synthesising any alcoholic beverages.

The humiliation continued on the bridge, where he resented the way Spock used the link to get his attention, indicating a lapse in his behaviour with a look or to bring him over to his science station, for a quiet word. However, he had to admit that it made it easier to convince the crew that he was the Kirk they had always known and any slight deviances could be blamed on his recent illness.

Unfortunately, all this made him feel as though he were under a microscope, ironically, one of the things Spock had been trying to avoid when he decided not to hand the double over to Starfleet. Worse still, Kirk suspected that the Vulcan was using the link to instil in him the strange feelings he had been experiencing lately. Not surprisingly, Spock had denied it.

Spock had also established a routine of instruction for the Captain. Because the ship was on route to a star base for some rest and recreation, Kirk's day-to-day duties were not arduous. So for an hour each day he was invited or, as he saw it, ordered to meet Spock in his quarters, where the Vulcan attempted to inculcate in him the necessary positive personality traits. The instruction sessions involved a variety of methods. Sometimes Spock repeated the technique of using Kirk's memories, at other times he taught him logic and also the beginnings of Vulcan meditation. Another method was to make Kirk review his personal logs, written prior to the split, so that he could recall the character and values of the man he used to be. As the personal logs were held on his own computer Kirk was allowed to remain in his quarters when looking through them. However, Spock didn't trust him completely, often using the link to check up on him. The Human resented the idea that Spock was trying to turn him into his own version of James T Kirk.

At the moment, Kirk was sitting cross-legged on Spock's bed, (a position he considered beneath the dignity of the captain of a starship), while the Vulcan sat stiffly in a nearby chair, his fingers steepled, his eyes closed in meditation. Kirk studied Spock's face. He had spent a lot of time with the Vulcan, over the past few weeks and he could tell that Spock was tired. Kirk knew that Vulcans could keep going for days without rest so he could only suppose that the added burden of the mind-link was to blame. He was surprised that he hadn't noticed before but acknowledged that, at the start, he had probably been too angry to notice anything but his own concerns. Back then he had delighted in making Spock aware of his hatred for him, through the link, and had even considered ways of removing the Vulcan and the mind-link along with him. But he had known it was impossible and that Spock would sense it through the link anyway. Besides, he was starting to appreciate his First Officer, especially since he had helped eradicate the uncontrollable fear that had once filled Kirk's mind. In answer to the threat posed by McCoy, he had decided that the best strategy was to go along with whatever his first officer wanted, because his goal now was to be able to pass any psychiatric test the doctor could throw at him. Then he would be safe from future threats or accusations. He thought Spock must be proud of his logical approach to the problem.

"You are not concentrating," Spock said suddenly, opening his eyes.

Strangely, Kirk felt sorry for him, knowing that the Vulcan always had to keep alert to what his charge was doing and thinking, as well as carrying out his own duties. He decided to take pity on him.

"I'm really beat," Kirk lied, "and I can hear my bed calling to me. Do you mind if we call it a day?" He yawned, for emphasis.

"That will be acceptable," Spock said, trying to hide the relief he felt at the opportunity to be alone for a while. He might even risk indulging in the Vulcan technique used for periods of complete rest. He hadn't anticipated what an onerous task he was taking on when he decided to keep Kirk's double on the Enterprise. Also, it would be illogical to deny that his human half was finding it hard to cope with the loss of his friend.

Apart from that he was troubled by guilt, in connection with his attitude to the deceased Kirk's predicament. He had backed him to the hilt, even before they knew there was a double on board but, once they had realised the situation, Spock had almost revelled in the fact that at last someone else was made to realise what it was like to be split in half. He had dwelt more on the parallels with his own Vulcan/Human dichotomy than on Kirk's feelings. In fact, he had trampled callously on Kirk's fears and weaknesses, and then tried to excuse his attitude by pointing out that it was just the way he was. At the time he had congratulated himself on behaving as a Vulcan but, with hindsight, he now wondered if he had been punishing Kirk, making him a scapegoat for all the times he had been hurt himself. The captain had been in a position where he was just as vulnerable as his hybrid First Officer and Spock had kicked him while he was down. Guilt was illogical and yet, for the moment, inescapable. And that was one of the reasons he had decided to help Kirk's double. It was difficult for him because the Double possessed none of the characteristics that had made him Spock's friend. Nevertheless, Spock realised that, when it came to running the Enterprise, Kirk had had no equal. He had proved that during the incident involving Balok. Spock recalled events on the bridge.

There were just four minutes left before the deadline for the destruction of the Enterprise and her crew. Because of his burgeoning friendship with Kirk, Spock had battened down the hatches even harder on his emotions. His Vulcan half had felt ashamed to call the human friend. But, now that they only had a few minutes of life left, it seemed appropriate to use Kirk's familiar name when he approached the Captain.

"Jim?"

Kirk voiced his incomprehension at the reaction of the alien ship. Surely they realised that the Enterprise posed them no threat.

"There must be something to do," Kirk said, "something I've overlooked,"

Spock knew his next words might be the last he ever spoke to Kirk and he could give him no hope.

"Chess," he said. "When one is outmatched the game is over. Checkmate."

"Is that your best recommendation?" Kirk asked angrily.

"I'm so..."The apology stuck in his throat asSpock froze with shock. Not only had he offended the man who was both his superior officer and his friend by giving up, but worse he had also betrayed a loss of emotional control. He schooled his features into the best Vulcan mask he could manage and, keeping his eyes focused somewhere on the other side of the bridge, he said, "I regret that I can find no other logical alternative."

With only three minutes left Kirk said "Not chess, Mr Spock, Poker,"and came up with a plan so unexpected that only James Kirk could have thought of it. For the sake of the ship and the friend he had once been, Spock was determined that Kirk would be that Captain of the Enterprise again, even if he couldn't be his friend.

A little later, Spock opened up the link to check that Kirk was sleeping, as he had said he would be. Finding images from the past in the human's mind, Spock assumed he was dreaming and quickly broke the link. If he had maintained it a little longer he would have realised that Kirk was musing over an old personal log entry; the last before Gary Mitchell's death. He was reviewing a game of chess he had played with Spock. Kirk grinned at the memory of the Vulcan's irritation at the illogical way he had played the game – and won. He was thinking about the pleasure he had felt at besting his First Officer when sadness flooded his mind at the loss of the friendship that had existed between them. He frowned at this strange idea. Was Spock influencing his thoughts? He shook his head and moved forward to the log entry detailing his reaction to Gary Mitchell's death. Had he really liked him that much?

Next day, on the bridge, Kirk received bad news in the form of a communication from Starfleet. The crew's period of R & R was postponed and the Enterprise ordered to Psi 2000. They were to carry out the evacuation of the scientific team, stationed on the surface, and to monitor the break-up of the planet. The latter required the ship to make a series of complicated and dangerous manoeuvres and Kirk was not best pleased at being given the assignment at this particular moment, when he was looking forward to R & R and the possibility of dodging Spock for a while. Thankfully for the sake of Kirk's future career, Spock was just in time to prevent him from telling the Admiral concerned what he could do with his orders.

With the Enterprise on course for Psi 2000 the Captain was busy on the bridge. In sickbay Spock, McCoy and Scott were holding a meeting to discuss Kirk's part in the Enterprise's upcoming mission.

"Well the fat's in the fire now," McCoy said. "Without R & R we haven't the time to bring the Captain up to scratch."

Spock suppressed a sigh. "It is true that I had hoped to have achieved more before the Captain had to deal with a Star Fleet assignment. However, there was always the possibility of R & R being postponed and I am prepared to carry on with the programme I have started, though it will necessarily be curtailed due to the amount of time the Captain will need to spend on the bridge."

"Can he handle the mission? That's the question. The other day I had Mr Leslie up here with a fractured ulna. He told me the Captain refused to have him relieved until the end of his shift."

"I am aware of the incident, Doctor. I realised immediately what the Captain had done and sent Mr Leslie to sickbay myself. The Captain will not make that mistake again."

"You hope," McCoy grumbled. "Does that mean we won't see a repeat of the fiasco over the emergency drill? Efficiency was at 98% yet the Captain still wasn't satisfied."

"I almost had a mutiny on my hands in Engineering," Scott complained.

"There have been problems but the link is working very well," Spock told them. "The mission is a straightforward one. The Captain is more than capable of calculating the manoeuvres needed to prevent the ship from spiralling down into the planet's atmosphere. Let us return to our stations. Mr Scott and I will have our hands full."

"And so will I," McCoy chipped in. "I want you to stay behind, Mr Spock. You're looking really tired these days. I knew that link would be bad for you. I'm going to fix you up with some shots. And no arguments," he said, as Spock opened his mouth to protest.

The cabin door swished open and Spock entered.

"I hope, I'm not disturbing you, Captain."

"What is it, Mr Spock?"

"The Enterprise will reach the planet Psi 2000 in precisely 2.47 hours. I wish to discuss with you the evacuation of the personnel from the observation station."

"What's the problem? I've already assigned a landing party, you and Tormolen. Are you questioning my decision, Mr Spock?"

"Captain, aren't you overlooking an important point?"

"No, I don't think so." What was the Vulcan getting at?

"I am uncertain of the maximum distance over which our link will operate effectively. Under the circumstances it would be wise for you to beam down with us."

"I can't possibly leave the Enterprise while she's in orbit around a planet that's about to disintegrate. She could be badly affected by the changes in gravity and magnetic field."

"At this early stage you will not be missed. Have you considered that the crew, and specifically the landing party, might be in danger if I leave you in command of the Enterprise, without an effective link?"

Kirk was stung by the casual reference to the fact that he'd once callously attempted to strand a landing party, condemning them to certain death, on a freezing planet. Was Spock influencing him to use logic? His doubts about the link came back full blast.

"All right, you've made your point," he said tightly.

Twenty-four hours later Spock was on his way to the Engineering section. Tormolen was dead, probably from the same thing that had killed the six lab crew stationed on Psi 2000. A number of the crew were also affected, including Sulu, who was confined to sickbay, and Riley, who was at that moment holed up in Engineering, singing "I'll Take you Home, Kathleen" for the third time. The Captain was relying on McCoy to find an antidote to whatever was devastating the crew, and on Scotty to wrest back control of the Enterprise from Riley. The Chief Engineer had already arranged for enough power to stabilise the ship, which was spiralling down toward the planet below and they now had approximately 20 minutes to get the Enterprise free from the planet's gravitational pull. When Spock arrived at Engineering, Scott was using a phaser to burn a hole in the wall, in an attempt to get at the door release mechanism.

Spock was just telling him that they couldn't afford a safety factor, when the ship's intercom sounded. "Mr, Spock, this is the Captain. Tell Scotty to get a move on."

Spock pressed the intercom button. "He is working as fast possible, Captain," he said patiently.

"What the hell did you think you were doing, Spock, sending Riley to sickbay without an escort?" Kirk said angrily. "Tell Mr Scott, I want Riley out of there, dead or alive, I don't care which."

Spock raised one eyebrow. "Surely you don't mean that, Captain."

Kirk could feel Spock through the link. Blast! "OK, ignore that. Go to sickbay and find out if Dr McCoy has come up with an antidote yet."

"I'm on my way," Spock said at the same time as he heard Kirk shout, "Uhura, can't you cut that blasted singing off?" Then the intercom was silent.

Meanwhile, in sickbay, McCoy had worked out what was wrong with the crew. The infection was carried in water from the planet surface and it was passed from person to person through perspiration. Once in the bloodstream it worked like alcohol, causing the centres of judgement and self-control to become depressed. He'd sent a sample of the antidote down to the medical lab but, when he tried to contact them to prepare more, there was no response. Fearing the technicians had been infected, he decided to set off for the lab to see to it himself. On the way he suddenly thought of Spock. If either he or the captain were infected, it could have a devastating effect on the link.

When Spock arrived in sickbay, he found only Nurse Chapel in attendance.

Scott finally got the door to engineering open. "Follow me through," Kirk said. "Put your phasers on stun. Don't fire unless he's armed."

Minutes later Scott was telling the Captain, "He's turned the engines off. They're stone-cold. I'll need at least 30 minutes."

"Isn't there anything you can do?" Kirk exploded.

"I canna change the laws of physics," Scotty told him. "You can't mix matter and anti-matter cold. We'd goup in the biggest explosion since..." Scotty tried to think of something comparable.

Kirk had no time for this. He searched his memory for something he'd heard of during his Academy days. "We can balance our engines with a controlled implosion," he yelled.

"That's just a theory, it's never been done."

"Spock will know what to do," Kirk decided. He pressed the ship's intercom button. "Mr Spock, come in, Mr Spock. Blast you! Spock, report to Engineering immediately!" There was no response. "Uhura?"

"Here, Captain."

"I'm going to look for Spock. Let me know if he reports in."

"Yes, Captain."

Spock was in the briefing room, trying desperately to keep his emotions under control. He thought about Christine. He hadn't known she loved him and he knew he must have hurt her because he couldn't, wouldn't, return her feelings for him. The Captain, on the other hand, hated him. Kirk had tried to keep it hidden but, like all the other emotions he couldn't control it had seeped through the link from time to time. He couldn't cope with the emotions bombarding him, making his feel, making him lose control. He had to remember he was a Vulcan and act like one. He sobbed and then took a shuddering breath, tried to square his shoulders, and sobbed again. "I am in control of my emotions," he told himself. It didn't work and he collapsed into a chair, still sobbing. He shook his head, trying to think. Perhaps going through a mathematical progression would help. "2, 4, 6, 6, 6, times..." It was no good. He put his folded arms on the table in front of him and laid his head on them, his face mirroring his anguish.

Kirk hurtled through the door, strode to his first officer, grabbed him by the shoulders and shook him. "What's wrong with you?" he asked.

"Christine loves me," Spock said with sadness. "And you hate me. I can't take the link any more – your hatred, your fear. I have to control my emotions."

"Spock, pull yourself together! We're all going to die. Don't you understand?"

"You don't understand. I've hurt so many people because I could never tell them how I felt. I was ashamed of my feelings for them."

Kirk shook him again. "Blast you, fight it, Spock!" he ordered, and slapped him. The surprise forced the Vulcan back into the chair.

Spock leapt up and punched the Captain, sending him crashing into the bulkhead. Kirk sprang to his feet, blood trickling from his lip. Rubbing his shoulder he faced the Vulcan. "You have to give Mr Scott the formula for a full power start!" he said.

Spock looked at him as if he were mad. "It can't be done," he said.

"I know the odds are ten thousand to one against us but we have to try."

Spock shook his head. "Captain," he said, "I've just realised that I lost the link while I was affected?"

Kirk was looking dazed. He'd been so busy trying to find Spock he had assumed that the Vulcan was controlling the rage he'd felt at being helpless to save the Enterprise. "Does that mean these strange feelings I have are part of me?"

"What is the nature of the feelings you have been experiencing?" Spock asked.

"From my memories I think they are feelings of friendship and," he realised. "I didn't want to be your friend because I thought you were making me feel that way and I resented it. I don't hate you anymore, Spock. I know now you were trying to help me."

"I have always been your friend," Spock assured him.

No sooner had Spock spoken than Kirk realised he had been infected through the contact of his hand on Spock's face, when he had slapped him. His expression quickly turned to one of fear. "I'm losing the ship," he said. "I can't lose her; she's all I've got. You're allowed to notice Yeoman Rand, all the men on board are allowed to notice her. I'm not even allowed near her. I hated you for that. I need a woman made of flesh to hold. Not like the Enterprise; I give, she takes."

Meanwhile the Vulcan had come to his senses.

"Captain, there is an intermix formula, it's never been tested. It's a theoretical relationship between time and anti-matter."

Kirk pulled himself together and seconds later he was heading for the bridge while Spock made for Engineering. As the Vulcan left he heard Kirk say, "I'll never lose you, never!" and realised the Captain was still thinking about the Enterprise. They had approximately 3 minutes to make it a reality.

The cold start forced the Enterprise into a dramatic acceleration. As she sped away from Psi 2000 it felt like the ship was about to break apart, especially when the life support systems died momentarily before coming back on line.

McCoy had injected Kirk with the antidote as he entered the bridge and the Captain was starting to feel back to normal. He looked round the bridge, once more in tune with the Enterprise.

Spock came out of the turbo-lift and moved swiftly to Kirk's side. "Are you all right, Jim?" he asked.

It was obvious from Kirk's smile that he was. "Thank you," he said softly. Spock raised one quizzical eyebrow. "You just called me 'Jim'," Kirk explained.

Spock gave him a look that made Kirk think he was about to say "fascinating". His confidence took a plunge. "I shouldn't have said anything. I realise I can never be the man you used to know," he said quietly, unwilling to draw attention to their conversation.

Spock placed a hand on Kirk's arm. "I have never considered you anything but that man, Jim," he said.

Kirk gave him a grateful smile. Then Sulu reported that they had been travelling faster than was possible in normal space.

"What's happening?" Kirk asked.

"The chronometer is running backwards, Captain."

In fact, before they were back on course, the ship had gone through a time warp and they ended up seventy-one hours in the past. As Spock pointed out, they could use the formula to go back in time to any planet, any era.

"We may risk it one day," Kirk said, looking at Spock to see if he was considering the opportunity to prevent the transporter malfunction that had split his Captain in two.

But Spock merely nodded and Kirk knew that he was content with the Captain he had. Reassured, Kirk knew that he could allow himself to trust the Vulcan First Officer. He knew that he wasn't quite where he needed to be yet but with Spock's help he had a chance of getting there.

THE END


End file.
